DEX: read_uleb128_bounded(), fix buffer-overflow
#1949
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This allows us to read ULEB128 encoded values close to the end of a buffer. This change fixes a heap-buffer-overflow in `load_encoded_method()`, found by fuzzing. In that method, the `fits_in_dex()` check is not sufficient, as each `uint32_t` can occupy up to 5 bytes in ULEB128 encoding. I did not replace all uses of `read_uleb128()` in `dex.c`, but follow-up changes should probably do that.
plusvic
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Aug 16, 2023
cblichmann
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This is a follow-up to PR VirusTotal#1949, replacing all remaingin uses of `read_uleb128()` in `dex.c`. It also fixes another heap-buffer-overflow, again found by fuzzing. Tested with `test-dex.c`
plusvic
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Aug 18, 2023
This is a follow-up to PR #1949, replacing all remaingin uses of `read_uleb128()` in `dex.c`. It also fixes another heap-buffer-overflow, again found by fuzzing. Tested with `test-dex.c`
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This allows us to read ULEB128 encoded values close to the end of a buffer.
This change fixes a heap-buffer-overflow in
load_encoded_method(), found by fuzzing. In that method, thefits_in_dex()check is not sufficient, as eachuint32_tcan occupy up to 5 bytes in ULEB128 encoding.I did not replace all uses of
read_uleb128()index.c, but follow-up changes should probably do that.